Breast cancer

Breast cancer is one of the most common cancers in women, with about one in eight women diagnosed by the age of 85. It can occur at any age but is most common in women over 40. Men can also develop breast cancer, although this is rare, and it is treated in the same way as breast cancer in women.

What is breast cancer?#

Breast cancer is the abnormal growth of cells in the breast. It usually starts in the lining of the breast ducts or lobules and can grow into cancerous (malignant) tumours.

Most breast cancers are found when they are invasive, meaning the cancer has spread from the ducts or lobules into the surrounding breast tissue. Invasive breast cancer can be early, locally advanced or advanced (metastatic). Advanced breast cancer is when cancer cells have spread beyond the breast and nearby lymph nodes to other parts of the body. About 5% of breast cancers are advanced when first diagnosed.

Risks and causes#

Many factors can increase your risk of breast cancer, but having them does not mean you will develop it. You can also have none of the known risk factors and still get breast cancer. The exact cause is unknown, but factors that seem to increase risk include:

• being female — the great majority of cases are diagnosed in women
• getting older — more than three quarters of breast cancers occur in women aged 50 and over
• a previous diagnosis of breast cancer
• several close relatives (mother, sister or daughter) who have had breast cancer, or close relatives on the same side of the family with prostate or pancreatic cancer
• certain breast conditions found on a mammogram, such as atypical ductal hyperplasia (most benign breast conditions do not increase risk)
• regular alcohol intake — limiting how much you drink can reduce this risk
• carrying more fatty tissue after menopause, which can raise estrogen levels
• using hormone therapy — the risk increases the longer you take it, but falls back within about two years of stopping
• in men, a rare genetic condition called Klinefelter syndrome

Risk assessment tools can help you understand your level of risk compared with the average for people your age. Talk to your doctor for more advice.

Early detection#

It is important for all women to get to know the normal look and feel of their breasts. Breasts change throughout life because of puberty, the menstrual cycle, pregnancy and breastfeeding. Breast cancer sometimes has no symptoms, so regular checks are important for women aged 40 and over.

A breast change does not usually mean cancer — nine out of 10 breast changes are not breast cancer — but see a doctor if you notice:

• a lump, lumpiness or thickening, especially in just one breast
• a change in the size or shape of the breast, or swelling
• swelling or discomfort in the armpit or near the collarbone
• a change to the nipple, such as a change in shape, crusting, sores, redness, pain, a clear or bloody discharge, or a nipple that turns inward when it used to stick out
• a change in the skin, such as dimpling, a rash, itchiness, a scaly appearance or unusual redness
• ongoing, unusual breast pain not related to your period

Some of these symptoms can occur without serious disease, but your doctor should check any unusual breast change. Early detection means treatment has a much better chance of success.

Screening mammography#

A screening mammogram is used to detect breast cancer early, when you are well and have no obvious breast symptoms. It can find cancers that are too small to be felt by you or your doctor. Mammograms taken at different times can be compared to show changes in breast tissue over time.

Many screening programs invite women in a target age range — commonly around 50 to 74 — for a screening mammogram every two years, and screening may also be available to women who are younger or older. Check what is recommended and available where you live.

Diagnosis#

Breast changes are investigated through a series of tests arranged by your doctor or specialist. Most are found to be benign (non-cancerous). If tests suggest you may have cancer, your doctor will refer you to a specialist to discuss treatment options. Initial tests may include:

• a physical examination of the breasts and armpits
• a diagnostic mammogram (an X-ray of the breast tissue)
• an ultrasound, which uses sound waves to scan the breast
• a breast MRI, mainly used for people at high risk or who have dense breasts or breast implants

If further tests are needed, one or more procedures may be used, including:

• fine needle aspiration — a very narrow needle withdraws cells from the area being tested
• core biopsy — a larger needle takes a tissue sample
• vacuum-assisted core biopsy — a needle attached to a suction instrument removes more tissue
• surgical biopsy — surgery under general anaesthetic removes the whole area for testing

Tests on breast tissue#

If a cancer is found, it can be checked for features that help plan treatment:

• Hormone receptor status — normal breast cells have estrogen and progesterone receptors. Cancers with too many of these are hormone-positive and are treated with hormone-blocking drugs.
• HER2 status — HER2 is a protein that controls how cells grow and divide. Cancers with too many HER2 receptors are HER2-positive and are often treated with chemotherapy and targeted treatments.
• Triple negative — this type does not have any of the three receptors commonly found on breast cancer cells (estrogen, progesterone or HER2). Chemotherapy is generally recommended for triple negative breast cancer.

If tests show you may have breast cancer, you may have further tests, such as blood tests, bone scans, CT scans or PET scans, to see whether it has spread. Not everyone needs all of these. Results can take a few days, and it is natural to feel anxious while you wait — it can help to talk to a close friend or relative about how you are feeling.

Treatment#

Treatment options include surgery, radiotherapy, chemotherapy, targeted therapy, hormone-blocking therapy and immunotherapy. Usually more than one is used. Treatment for breast cancer in men is similar to, and as effective as, the treatment for women. The right approach depends on several factors, including:

• the stage of the cancer (whether it is confined to the breast or has spread)
• the grade of the cancer cells — grade 1 (low grade) cells look a little different from normal and grow slowly; grade 2 (intermediate) grow faster; grade 3 (high grade) look very different and grow fast
• the results of tests on the cancer cells (such as HER2 status or triple negative)
• your age, general health and personal preferences

Surgery#

An operation to remove the cancer, surrounding breast tissue and often the nearby lymph nodes is usually the preferred first treatment. Options include:

• Breast-conserving surgery — a smaller operation removes the cancer, some surrounding tissue and usually some lymph nodes, leaving most of the breast intact. It is often followed by a course of radiotherapy.
• Mastectomy — the entire breast is removed, along with some or all of the lymph nodes from the armpit.

Women who have a mastectomy may choose to have reconstruction (at the same time or later), or may choose not to. Reconstruction options include silicone gel or saline-filled implants, or using your own muscle and skin to create a breast-like shape. Women who do not have reconstruction may use a breast form or prosthesis — pads worn inside the bra to restore balance and look like a natural breast under clothes.

All surgery has some risks. Possible side effects of breast surgery include fatigue, shoulder stiffness, numbness and tingling, fluid build-up around the scar or armpit (seroma), swelling of the arm (lymphoedema), post-mastectomy pain and cording (axillary web syndrome). These are not common, but it is worth being aware of them.

Other treatments#

Depending on the cancer, other options can include:

• Radiotherapy — uses radiation to kill any remaining cancer cells. Women who have had breast-conserving surgery often have a course. Side effects can include short-term reddening of the skin, like sunburn, or longer-term thickening of the skin.
• Chemotherapy — cancer-killing medication given into a vein. It can be offered as an extra treatment alongside surgery, radiotherapy or both. Side effects depend on the medication but can include nausea, diarrhoea and hair loss.
• Hormone-blocking treatment — many breast cancers are influenced by estrogen and progesterone. Blocking these hormones can reduce the chance of the cancer coming back.
• Targeted therapy — uses drugs that target specific proteins or enzymes involved in cancer growth. For example, trastuzumab is used for HER2-positive breast cancer.
• Immunotherapy — medicines that strengthen the immune system to fight cancer. A drug called pembrolizumab may be used for certain triple negative breast cancers.

Complementary therapies such as massage, relaxation and acupuncture are designed to be used alongside conventional treatment and can increase your sense of control, decrease stress and anxiety, and improve your mood. Let your doctor know about any you are using or considering, as some may not be safe or evidence-based. Alternative therapies are used instead of conventional treatment; they are unlikely to be scientifically tested, may prevent successful treatment and can be harmful.

All treatments can cause side effects. Many are temporary, but some may be permanent, and your medical team will discuss these with you before you start treatment.

Research and clinical trials#

Early detection and better treatment have improved survival for people with breast cancer, and research is ongoing. Clinical trials can test promising new treatments or new ways of combining care, and can also explore the emotional and physical effects of breast cancer and ways to improve quality of life. Talk to your doctor about whether a particular trial may be suitable for you.

Living with breast cancer#

Breast cancer can affect how you feel about yourself and make you feel self-conscious or less confident. These feelings are common, so give yourself time to adapt. If you would like to talk things through, ask your doctor for a referral to a counsellor or speak with a cancer nurse. Caring for someone with breast cancer can also be difficult and emotional, and support is available for carers too.

If breast cancer is diagnosed at a later stage, it may have spread to the point where a cure is no longer possible. Treatment may then be given to slow its growth and improve quality of life by relieving symptoms such as pain, nausea and vomiting — this is called palliative treatment.

Key points#

• Breast cancer can occur at any age but is most common in women over 40.
• Many factors can increase your risk, but you can also have no known risk factors and still develop it.
• Get to know the normal look and feel of your breasts, and see a doctor about any unusual change.
• Early detection through awareness and screening gives the best chance of effective treatment.
• Treatment may combine surgery, radiotherapy, chemotherapy, targeted therapy, hormone-blocking therapy and immunotherapy, depending on the cancer and your circumstances.

Where to get help#